1. Field of the Invention
The present invention relates to a method and apparatus for judging deformation of a vertebral body. More particularly, the present invention relates to a method and apparatus for judging deformation of a vertebral body which is one of the bones forming the spinal column. A judgment of the presence of vertebral body deformation accompanied by osteoporosis, as well as a classification of the deformation, is very important for grasping the progress of osteoporosis and for confirmation of the effect of therapy.
2. Description of the Related Art
In the prior art, the presence of deformation of a vertebral body which is one of the bones forming the spinal column has been judged by a physician by visual observation of the profile X-ray images of thoracic vertebrae or lumbar vertebrae. However, compared with a fracture of the so called long bones such as the femur, tibia, radius, ulna, etc., a judgment of vertebral deformation is difficult since this is usually a wedge-shaped deformation, pressure fracture, depressed fracture, etc., and any judgment inevitably involves individual differences. Also, even if an attempt is made to monitor changes over a period of time, for confirmation of the effect of therapy, because the deformation cannot be quantified, progress of the deformation, if any, cannot be easily determined.
Also, although a method has been reported in which the ratio (a/d) of the central length (a) to the front brim length (d) of the third lumbar vertebrae is determined as the index (Lumbar Spine Score) for the degree of bone atrophy, or a change in the longitudinal and lateral bone beams of the third lumbar vertebrae is observed as the index for the degree of bone atrophy (severity classified by Jikei University), or a judgment of the fracture of a vertebral body is made by measurement of the central length (a), front brim length (d) and rear brim length (c) of a vertebral body The New England Journal of Medicine, vol. 306, 446 (Feb. 25, 1982), a method for classifying the type of deformation of a vertebral body has not heretofore been known.